1. The Field of the Invention
This invention relates to liquid flow control devices.
2. The Relevant Technology
Many different forms of valving arrangements are known for controlling liquid flow through a port or passageway. Such arrangements include the use of liquid swellable materials which enlarge with contact with a liquid to obstruct a passageway or port and which shrink when not in contact with a liquid to allow flow through the passageway or port. Such arrangements can be utilized in automatic on/off systems for controlling liquid flow such as systems for watering for horticultural or agricultural applications.